An ETSI change request to GSM 04.14 (ETSI Document 2-00-1004) and the accompanying liaison statement response (ETSI Document 2-00-1007) has made significant changes to the general packet radio service (GPRS) test modes previously envisaged. As a consequence, there are some changes to the handling of the downlink temporary block flow (TBF) which preclude the making of block error ratio (BLER) measurements within the test mode. BLER measurements require a sustained flow of data blocks while the measurement is being made.
The ETSI Test Modes normally require only a GPRS mobility management service access point (GMM SAP) above the logical link control (LLC) layer, thus limiting the processing burden required to implement these test modes. If a full data connection were made, by adding a sub-network dependent convergence protocol (SNDCP) SAP and higher layers, to enable the BLER measurements which are no longer feasible in the test modes, there would be a resulting substantial and undesirable increase in the processing burden solely for the purpose of making these measurements.
It is an object of this invention to facilitate GPRS BLER measurements without imposing this extra processing burden.